1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2013 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 #include "path-util.h"
26 #include "cgroup-util.h"
29 void cgroup_context_init(CGroupContext *c) {
32 /* Initialize everything to the kernel defaults, assuming the
33 * structure is preinitialized to 0 */
36 c->memory_limit = c->memory_soft_limit = (uint64_t) -1;
37 c->blockio_weight = 1000;
40 void cgroup_context_free_device_allow(CGroupContext *c, CGroupDeviceAllow *a) {
44 LIST_REMOVE(CGroupDeviceAllow, device_allow, c->device_allow, a);
49 void cgroup_context_free_blockio_device_weight(CGroupContext *c, CGroupBlockIODeviceWeight *w) {
53 LIST_REMOVE(CGroupBlockIODeviceWeight, device_weights, c->blockio_device_weights, w);
58 void cgroup_context_free_blockio_device_bandwidth(CGroupContext *c, CGroupBlockIODeviceBandwidth *b) {
62 LIST_REMOVE(CGroupBlockIODeviceBandwidth, device_bandwidths, c->blockio_device_bandwidths, b);
67 void cgroup_context_done(CGroupContext *c) {
70 while (c->blockio_device_weights)
71 cgroup_context_free_blockio_device_weight(c, c->blockio_device_weights);
73 while (c->blockio_device_bandwidths)
74 cgroup_context_free_blockio_device_bandwidth(c, c->blockio_device_bandwidths);
76 while (c->device_allow)
77 cgroup_context_free_device_allow(c, c->device_allow);
80 void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
81 CGroupBlockIODeviceBandwidth *b;
82 CGroupBlockIODeviceWeight *w;
88 prefix = strempty(prefix);
91 "%sCPUAccounting=%s\n"
92 "%sBlockIOAccounting=%s\n"
93 "%sMemoryAccounting=%s\n"
95 "%sBlockIOWeight%lu\n"
96 "%sMemoryLimit=%" PRIu64 "\n"
97 "%sMemorySoftLimit=%" PRIu64 "\n"
98 "%sDevicePolicy=%s\n",
99 prefix, yes_no(c->cpu_accounting),
100 prefix, yes_no(c->blockio_accounting),
101 prefix, yes_no(c->memory_accounting),
102 prefix, c->cpu_shares,
103 prefix, c->blockio_weight,
104 prefix, c->memory_limit,
105 prefix, c->memory_soft_limit,
106 prefix, cgroup_device_policy_to_string(c->device_policy));
108 LIST_FOREACH(device_allow, a, c->device_allow)
110 "%sDeviceAllow=%s %s%s%s\n",
113 a->r ? "r" : "", a->w ? "w" : "", a->m ? "m" : "");
115 LIST_FOREACH(device_weights, w, c->blockio_device_weights)
117 "%sBlockIODeviceWeight=%s %lu",
122 LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) {
123 char buf[FORMAT_BYTES_MAX];
128 b->read ? "BlockIOReadBandwidth" : "BlockIOWriteBandwidth",
130 format_bytes(buf, sizeof(buf), b->bandwidth));
134 static int lookup_blkio_device(const char *p, dev_t *dev) {
143 log_warning("Couldn't stat device %s: %m", p);
147 if (S_ISBLK(st.st_mode))
149 else if (major(st.st_dev) != 0) {
150 /* If this is not a device node then find the block
151 * device this file is stored on */
154 /* If this is a partition, try to get the originating
156 block_get_whole_disk(*dev, dev);
158 log_warning("%s is not a block device and file system block device cannot be determined or is not local.", p);
165 static int whitelist_device(const char *path, const char *node, const char *acc) {
166 char buf[2+DECIMAL_STR_MAX(dev_t)*2+2+4];
173 if (stat(node, &st) < 0) {
174 log_warning("Couldn't stat device %s", node);
178 if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
179 log_warning("%s is not a device.", node);
185 S_ISCHR(st.st_mode) ? 'c' : 'b',
186 major(st.st_rdev), minor(st.st_rdev),
189 r = cg_set_attribute("devices", path, "devices.allow", buf);
191 log_warning("Failed to set devices.allow on %s: %s", path, strerror(-r));
196 void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const char *path) {
205 if (mask & CGROUP_CPU) {
206 char buf[DECIMAL_STR_MAX(unsigned long) + 1];
208 sprintf(buf, "%lu\n", c->cpu_shares);
209 r = cg_set_attribute("cpu", path, "cpu.shares", buf);
211 log_warning("Failed to set cpu.shares on %s: %s", path, strerror(-r));
214 if (mask & CGROUP_BLKIO) {
215 char buf[MAX3(DECIMAL_STR_MAX(unsigned long)+1,
216 DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(unsigned long)*1,
217 DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+1)];
218 CGroupBlockIODeviceWeight *w;
219 CGroupBlockIODeviceBandwidth *b;
221 sprintf(buf, "%lu\n", c->blockio_weight);
222 r = cg_set_attribute("blkio", path, "blkio.weight", buf);
224 log_warning("Failed to set blkio.weight on %s: %s", path, strerror(-r));
226 /* FIXME: no way to reset this list */
227 LIST_FOREACH(device_weights, w, c->blockio_device_weights) {
230 r = lookup_blkio_device(w->path, &dev);
234 sprintf(buf, "%u:%u %lu", major(dev), minor(dev), w->weight);
235 r = cg_set_attribute("blkio", path, "blkio.weight_device", buf);
237 log_error("Failed to set blkio.weight_device on %s: %s", path, strerror(-r));
240 /* FIXME: no way to reset this list */
241 LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) {
245 r = lookup_blkio_device(b->path, &dev);
249 a = b->read ? "blkio.throttle.read_bps_device" : "blkio.throttle.write_bps_device";
251 sprintf(buf, "%u:%u %" PRIu64 "\n", major(dev), minor(dev), b->bandwidth);
252 r = cg_set_attribute("blkio", path, a, buf);
254 log_error("Failed to set %s on %s: %s", a, path, strerror(-r));
258 if (mask & CGROUP_MEMORY) {
259 char buf[DECIMAL_STR_MAX(uint64_t) + 1];
261 sprintf(buf, "%" PRIu64 "\n", c->memory_limit);
262 r = cg_set_attribute("memory", path, "memory.limit_in_bytes", buf);
264 log_error("Failed to set memory.limit_in_bytes on %s: %s", path, strerror(-r));
266 sprintf(buf, "%" PRIu64 "\n", c->memory_soft_limit);
267 cg_set_attribute("memory", path, "memory.soft_limit_in_bytes", buf);
269 log_error("Failed to set memory.limit_in_bytes on %s: %s", path, strerror(-r));
272 if (mask & CGROUP_DEVICE) {
273 CGroupDeviceAllow *a;
275 if (c->device_allow || c->device_policy != CGROUP_AUTO)
276 r = cg_set_attribute("devices", path, "devices.deny", "a");
278 r = cg_set_attribute("devices", path, "devices.allow", "a");
280 log_error("Failed to reset devices.list on %s: %s", path, strerror(-r));
282 if (c->device_policy == CGROUP_CLOSED ||
283 (c->device_policy == CGROUP_AUTO && c->device_allow)) {
284 static const char auto_devices[] =
288 "/dev/random\0" "rw\0"
289 "/dev/urandom\0" "rw\0";
293 NULSTR_FOREACH_PAIR(x, y, auto_devices)
294 whitelist_device(path, x, y);
297 LIST_FOREACH(device_allow, a, c->device_allow) {
312 whitelist_device(path, a->path, acc);
317 CGroupControllerMask cgroup_context_get_mask(CGroupContext *c) {
318 CGroupControllerMask mask = 0;
320 /* Figure out which controllers we need */
322 if (c->cpu_accounting || c->cpu_shares != 1024)
323 mask |= CGROUP_CPUACCT | CGROUP_CPU;
325 if (c->blockio_accounting ||
326 c->blockio_weight != 1000 ||
327 c->blockio_device_weights ||
328 c->blockio_device_bandwidths)
329 mask |= CGROUP_BLKIO;
331 if (c->memory_accounting ||
332 c->memory_limit != (uint64_t) -1 ||
333 c->memory_soft_limit != (uint64_t) -1)
334 mask |= CGROUP_MEMORY;
336 if (c->device_allow || c->device_policy != CGROUP_AUTO)
337 mask |= CGROUP_DEVICE;
342 static CGroupControllerMask unit_get_cgroup_mask(Unit *u) {
345 c = unit_get_cgroup_context(u);
349 return cgroup_context_get_mask(c);
352 static CGroupControllerMask unit_get_members_mask(Unit *u) {
353 CGroupControllerMask mask = 0;
359 SET_FOREACH(m, u->dependencies[UNIT_BEFORE], i) {
361 if (UNIT_DEREF(m->slice) != u)
364 mask |= unit_get_cgroup_mask(m) | unit_get_members_mask(m);
370 static CGroupControllerMask unit_get_siblings_mask(Unit *u) {
373 if (!UNIT_ISSET(u->slice))
376 /* Sibling propagation is only relevant for weight-based
377 * controllers, so let's mask out everything else */
378 return unit_get_members_mask(UNIT_DEREF(u->slice)) &
379 (CGROUP_CPU|CGROUP_BLKIO|CGROUP_CPUACCT);
382 static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
385 bool is_in_hash = false;
389 path = unit_default_cgroup_path(u);
393 r = hashmap_put(u->manager->cgroup_unit, path, u);
399 log_error("cgroup %s exists already: %s", path, strerror(-r));
403 /* First, create our own group */
404 r = cg_create_with_mask(mask, path);
406 log_error("Failed to create cgroup %s: %s", path, strerror(-r));
408 /* Then, possibly move things over */
409 if (u->cgroup_path && !streq(path, u->cgroup_path)) {
410 r = cg_migrate_with_mask(mask, u->cgroup_path, path);
412 log_error("Failed to migrate cgroup %s: %s", path, strerror(-r));
416 /* And remember the new data */
417 free(u->cgroup_path);
418 u->cgroup_path = path;
421 u->cgroup_realized = true;
422 u->cgroup_mask = mask;
427 static int unit_realize_cgroup_now(Unit *u) {
428 CGroupControllerMask mask;
432 if (u->in_cgroup_queue) {
433 LIST_REMOVE(Unit, cgroup_queue, u->manager->cgroup_queue, u);
434 u->in_cgroup_queue = false;
437 mask = unit_get_cgroup_mask(u) | unit_get_members_mask(u) | unit_get_siblings_mask(u);
438 mask &= u->manager->cgroup_supported;
440 if (u->cgroup_realized &&
441 u->cgroup_mask == mask)
444 /* First, realize parents */
445 if (UNIT_ISSET(u->slice))
446 unit_realize_cgroup_now(UNIT_DEREF(u->slice));
448 /* And then do the real work */
449 return unit_create_cgroups(u, mask);
452 static void unit_add_to_cgroup_queue(Unit *u) {
454 if (u->in_cgroup_queue)
457 LIST_PREPEND(Unit, cgroup_queue, u->manager->cgroup_queue, u);
458 u->in_cgroup_queue = true;
461 unsigned manager_dispatch_cgroup_queue(Manager *m) {
465 while ((i = m->cgroup_queue)) {
466 assert(i->in_cgroup_queue);
468 if (unit_realize_cgroup_now(i) >= 0)
469 cgroup_context_apply(unit_get_cgroup_context(i), i->cgroup_mask, i->cgroup_path);
477 static void unit_queue_siblings(Unit *u) {
480 /* This adds the siblings of the specified unit and the
481 * siblings of all parent units to the cgroup queue. (But
482 * neither the specified unit itself nor the parents.) */
484 while ((slice = UNIT_DEREF(u->slice))) {
488 SET_FOREACH(m, slice->dependencies[UNIT_BEFORE], i) {
492 if (UNIT_DEREF(m->slice) != slice)
495 unit_add_to_cgroup_queue(m);
502 int unit_realize_cgroup(Unit *u) {
508 c = unit_get_cgroup_context(u);
512 /* So, here's the deal: when realizing the cgroups for this
513 * unit, we need to first create all parents, but there's more
514 * actually: for the weight-based controllers we also need to
515 * make sure that all our siblings (i.e. units that are in the
516 * same slice as we are) have cgroup too. Otherwise things
517 * would become very uneven as each of their processes would
518 * get as much resources as all our group together. This call
519 * will synchronously create the parent cgroups, but will
520 * defer work on the siblings to the next event loop
523 /* Add all sibling slices to the cgroup queue. */
524 unit_queue_siblings(u);
526 /* And realize this one now */
527 r = unit_realize_cgroup_now(u);
529 /* And apply the values */
531 cgroup_context_apply(c, u->cgroup_mask, u->cgroup_path);
536 void unit_destroy_cgroup(Unit *u) {
544 r = cg_trim_with_mask(u->cgroup_mask, u->cgroup_path, !unit_has_name(u, SPECIAL_ROOT_SLICE));
546 log_debug("Failed to destroy cgroup %s: %s", u->cgroup_path, strerror(-r));
548 hashmap_remove(u->manager->cgroup_unit, u->cgroup_path);
550 free(u->cgroup_path);
551 u->cgroup_path = NULL;
552 u->cgroup_realized = false;
557 pid_t unit_search_main_pid(Unit *u) {
558 _cleanup_fclose_ FILE *f = NULL;
559 pid_t pid = 0, npid, mypid;
566 if (cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, &f) < 0)
570 while (cg_read_pid(f, &npid) > 0) {
576 /* Ignore processes that aren't our kids */
577 if (get_parent_of_pid(npid, &ppid) >= 0 && ppid != mypid)
581 /* Dang, there's more than one daemonized PID
582 in this group, so we don't know what process
583 is the main process. */
594 int manager_setup_cgroup(Manager *m) {
595 _cleanup_free_ char *path = NULL;
601 /* 0. Be nice to Ingo Molnar #628004 */
602 if (path_is_mount_point("/sys/fs/cgroup/systemd", false) <= 0) {
603 log_warning("No control group support available, not creating root group.");
607 /* 1. Determine hierarchy */
608 free(m->cgroup_root);
609 m->cgroup_root = NULL;
611 r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &m->cgroup_root);
613 log_error("Cannot determine cgroup we are running in: %s", strerror(-r));
617 /* Already in /system.slice? If so, let's cut this off again */
618 if (m->running_as == SYSTEMD_SYSTEM) {
619 e = endswith(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE);
624 /* And make sure to store away the root value without trailing
625 * slash, even for the root dir, so that we can easily prepend
627 if (streq(m->cgroup_root, "/"))
628 m->cgroup_root[0] = 0;
631 r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, NULL, &path);
633 log_error("Cannot find cgroup mount point: %s", strerror(-r));
637 log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
639 /* 3. Install agent */
640 if (m->running_as == SYSTEMD_SYSTEM) {
641 r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH);
643 log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
645 log_debug("Installed release agent.");
647 log_debug("Release agent already installed.");
650 /* 4. Realize the system slice and put us in there */
651 if (m->running_as == SYSTEMD_SYSTEM) {
652 a = strappenda(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE);
653 r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, a, 0);
655 r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, 0);
657 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
661 /* 5. And pin it, so that it cannot be unmounted */
662 if (m->pin_cgroupfs_fd >= 0)
663 close_nointr_nofail(m->pin_cgroupfs_fd);
665 m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK);
667 log_error("Failed to open pin file: %m");
671 /* 6. Figure out which controllers are supported */
672 m->cgroup_supported = cg_mask_supported();
677 void manager_shutdown_cgroup(Manager *m, bool delete) {
680 /* We can't really delete the group, since we are in it. But
682 if (delete && m->cgroup_root)
683 cg_trim(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, false);
685 if (m->pin_cgroupfs_fd >= 0) {
686 close_nointr_nofail(m->pin_cgroupfs_fd);
687 m->pin_cgroupfs_fd = -1;
690 free(m->cgroup_root);
691 m->cgroup_root = NULL;
694 Unit* manager_get_unit_by_cgroup(Manager *m, const char *cgroup) {
701 u = hashmap_get(m->cgroup_unit, cgroup);
715 u = hashmap_get(m->cgroup_unit, p);
721 Unit *manager_get_unit_by_pid(Manager *m, pid_t pid) {
722 _cleanup_free_ char *cgroup = NULL;
730 r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup);
734 return manager_get_unit_by_cgroup(m, cgroup);
737 int manager_notify_cgroup_empty(Manager *m, const char *cgroup) {
744 u = manager_get_unit_by_cgroup(m, cgroup);
746 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
748 if (UNIT_VTABLE(u)->notify_cgroup_empty)
749 UNIT_VTABLE(u)->notify_cgroup_empty(u);
751 unit_add_to_gc_queue(u);
758 static const char* const cgroup_device_policy_table[_CGROUP_DEVICE_POLICY_MAX] = {
759 [CGROUP_AUTO] = "auto",
760 [CGROUP_CLOSED] = "closed",
761 [CGROUP_STRICT] = "strict",
764 DEFINE_STRING_TABLE_LOOKUP(cgroup_device_policy, CGroupDevicePolicy);